Modern, high speed, automated concrete block plants and concrete paver plants make use of concrete block molds that are open at the top and bottom. These molds are mounted in machines which cyclically station a pallet below the mold to close the bottom of the mold, deliver dry cast concrete into the mold through the open top of the mold, densify and compact the concrete by a combination of vibration and pressure, and strip the uncured blocks from the mold by a relative vertical movement of the mold and the pallet. Once the blocks are stripped from the mold they are protected until they are sufficiently hardened to permit handling without damage. The concrete blocks thus hardened are cured in a curing yard to permit complete moisturization for at least twenty-one days.
For efficient high-volume production, concrete block molds are typically configured to produce multiple blocks simultaneously. A concrete block mold generally comprises side walls and end walls that define the periphery of a mold cavity. Within this mold cavity, division plates may be used to sub-divide the mold cavity into a plurality of block-forming cavities. Further, movable side walls may be used to form the side faces of the block-forming cavity. The division plates are generally rectangular-shaped plates attached to the side walls of the mold. Further, the side walls of the block cavity and the division plates may be covered with replaceable mold face linings to protect the mold components from abrasive wear.
Concrete blocks fabricated by the automated processes described above are often used in the construction of vertical walls, such as sitting walls, or set-back retaining walls for securing earth embankments against sliding and slumping. The blocks, often referred to as wallstones are stacked on each other and located in rows to form a wall. The wall structure can have a variety of shapes, such as linear, concave, and convex curved, serpentine and circular to conform to the landscape utilization. Each wallstone may have one or more attractive and decorative faces. The decorative faces can be smooth, serrated, horizontally grooved, vertically grooved, diagonally grooved, checkerboard or have an aggregate appearance. The front face of the block can be broken apart concrete or broken irregular pattern. The wallstone may be of any desired color including gray or earth tones and the like.
Each wallstone may have a generally flat top and bottom surface so that the rows of wallstones can be stacked or superimposed on top of each other. The adjacent rows of blocks may be connected together with rods or pins. Each block has one or more passages extending from the top surface to the bottom surface to accommodate the rods or pins. Rows of wallstones overlap each other so that each wallstone is pinned to adjacent wallstones located in adjacent courses of wallstone above and below. Multiple passages may be provided to the wallstones to add versatility so that each wallstone may be used in the construction of a vertical wall or a set-back wall.
For example, the wallstone may be fabricated to be versatile by providing six passages, four to be utilized for the construction of a set-back wall and two to be utilized for the construction of a vertical wall. To construct a set-back wall, after a first layer of wallstone is set and leveled in all directions to create a base, a subsequent course is added such that the two front passages of the subsequent layer wallstones are aligned above a pocket (also referred to as an “offset pocket”) located in the wallstones in the course below, to create a slight offset. After the wallstones are set and visually aligned, pins are dropped in these two holes and into the pockets in the wallstones of the base layer. This process is repeated as subsequent courses are added above previous courses to construct a set-back wall. In this manner, the wallstones become interlocked together, adding strength and integrity to the overall wall structure. To construct a vertical wall, the two passages located in the pocket of the wallstones of the subsequent course are aligned above the pocket of the wallstones in the previous course, and pins are dropped in these two holes and into the pocket in the wallstones of the previous course.
A common drawback is that during fabrication of the wallstones, debris created during the fabrication process can become lodged in the passages. If not removed quickly, the debris will cure within the passages and create obstructions therein, thus preventing use of the interlocking feature of the wallstones. Currently, the method for cleaning the passages of such debris involves manually inserting a dowel into each of these passages after the wallstone is stripped from the mold within the production environment and which adds to the overall cost and increases safety concerns. Such manual debris removal from the passages has other disadvantages. It is a delicate operation requiring a certain amount of dexterity to avoid damaging the passages of uncured wallstones. Also, the current manual cleaning requires added labor expressly dedicated to this particular task to keep pace with the high volume of wallstone being produced by the automated process. Thus, the debris removal device of the present invention offers significant advantages over the current manual cleaning described above. The debris removal device of the present invention is operative to direct a flow of pressurized fluid, such as air through a plurality of outlets and through the passages of wallstones as the wall stones are conveyed after being stripped from the mold. The device of the present invention is automated and may be integrated into the concrete block manufacturing process, thus eliminating the need for increased labor. Also, the device of the present invention can remove debris from multiple passages simultaneously to keep pace with the rate of automated production. Also, the device will substantially reduce the potential for damage to the wallstone passages.